* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    width: 100%;
    height: 100%;
}

.game {
    width: 800px;
    height: 600px;
    position: relative;
    margin: 0 auto;
    overflow: hidden;
    border: 2px solid #000;
    border-radius: 5px;
}
.pause {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    color: #fff;
    font-size: 50px;
    text-align: center;
    line-height: 600px;
    display: block;
}
.bird {
    width: 34px;
    height: 24px;
    background-image: url(./img/bird.png);
    position: absolute;
    left: 120px;
    top: 120px;
}
.swing1 {
    background-position: -8px -10px;
}
.swing2 {
    background-position: -60px -10px;
}
.swing3 {
    background-position: -113px -10px;
}

.sky {
    position: absolute;
    top: 0;
    left: 0;
    width: 200%;
    height: 100%;
    background-image: url(./img/sky.png);
    background-size: 100% 100%;
}
.land {
    width: 200%;
    height: 116px;
    background-image: url(./img/land.png);
    position: absolute;
    left: 0;
    bottom: 0;
}
.pipe {
    width: 52px;
    position: absolute;
}
.pipeUp {
    background-image: url(./img/pipeDown.png);
    top: 0;
    left: 400px;
    background-position: bottom;
    height: 200px;
}
.pipeDown {
    background-image: url(./img/pipeUp.png);
    bottom: 116px;
    left: 400px;
    height: 120px;
}
.info {
    text-align: center;
    margin-top: 5px;
}
